public async Task PatchTodoItem_WithValidId_ShouldReturnNoContent() { // Arrange var mockService = new Mock <ITodoItemService>(); var patch = new JsonPatchDocument <TodoItemDTO>(); mockService.Setup(service => service.PatchTodoItemAsync(1, patch)) .ReturnsAsync(new TodoItem()); var controller = new TodoController(mockService.Object); // Act var result = await controller.PatchTodoItem(1, patch); // Assert var viewResult = Assert.IsType <ActionResult <TodoItem> >(result); var noContentResult = Assert.IsType <NoContentResult>(viewResult.Result); Assert.Equal((int)HttpStatusCode.NoContent, noContentResult.StatusCode); }